The present invention relates to electrical power supplies, and more particularly, to a power supply in which the explosive removal of a permanent magnet from a coil produces a single-pulse, high voltage signal.
There are many commercial and military applications which require a brief, single-pulse, high voltage electrical signal under circumstances where connection to a utility power grid is either impossible or undesirable. For example, under battlefield conditions such a signal may be required to trigger a high power microwave pulse. Batteries and other conventional portable power supplies are not viable alternatives because they are too bulky and/or expensive.
The following U.S. Patents were uncovered in a patentability search conducted in regard to my invention.
U.S. Pat. No. 2,544,077 of Gardner discloses a so-called "surge generator" in which a gun fires a projectile 6 through magnetizable barrel sections 3 and 4 separated by a gap 5 surrounded by a coil 8. The gap 5 is spanned or bridged by a permanent magnet 7. When the projectile reaches the gap, it short circuits the magnetic lines of force from the magnet through the gap, inducing a voltage in the coil, thereby lighting a gas discharge lamp 22. As the projectile leaves the gap, it induces a voltage of opposite polarity in the coil, again lighting the lamp. The apparatus is reusable.
U.S. Pat. No. 2,825,863 of Krupen discloses another system in which a permanent magnet 8 is moved a short distance by detonation of an explosive primer to induce an electrical charge in a coil 6 which is stored in a capacitor 37.
U.S. Pat. No. 3,257,905 of Weisman et al. discloses a coil apparatus removably connectable to the end of the barrel of an M-1 rifle. A permanent magnet body 24, positioned at one end of the coil apparatus adjacent the tip of the barrel, is driven through the coil at a velocity of 180 feet per second by firing a blank cartridge in the rifle. The coil apparatus is reloadable with additional magnetic bodies 24. It can generate an output signal of 56 volts and 30 amperes using a magnetic body measuring three inches in length by three-quarters of an inch in diameter, weighing 0.3 pounds and having a field strength of 10,500 gauss.
U.S. Pat. No. 3,337,760 of Allport discloses a generator in which a solid rocket motor 19 or a rifle cartridge 181/182 are used to propel a metal slug 18 or 181 down a casing 20 through a transverse magnetic field provided by electromagnets, permanent magnets or solenoid coils. The slug may be a one centimeter cube of copper which may travel at a velocity of 1,000 meters per second through a magnetic field of 10,000 gauss to thereby produce a signal of ten volts at three million amperes. Conductors 13 and 14 are provided with terminals 15 and 16 for tapping the power when the cube connects the terminals by passing therebetween at high velocity.
U.S. Pat. No. 3,500,078 of Buser et al. discloses a pulse generator in which a strong magnetic field generated by a superconducting magnet requiring cryogenic fluids is interrupted by explosively driving a coil or other electrically conductive member past the field. A shell 52 is loaded in the barrel 42 of a breech loaded gun 50. Detonation of the shell sends coil 20 and piston 40 down rails 38 and 39 through the magnetic field emanating from superconducting coil 14 adjacent to the rails. Column 4, lines 45 et seq. indicate that the transfer of large current pulses from the fast moving load coil 20 to a stationary load "sometimes proves mechanically awkward." Velocities, signal voltages and currents are not specified.
U.S. Pat. No. 3,636,390 of Stauder et al. discloses a pulse generator in which an explosive charge 18 yields a large gas volume that causes a magnetic member 28 to move within a housing 10 past coils 24. Velocities, signal voltages and currents are not specified.
U.S. Pat. No. 4,594,521 of Schlicher discloses a repeatable electric pulse generator in which explosive propellants drive a permanent magnet attached to a piston rod inside a barrel. The magnet is disposed between the poles of a magnetic circuit in a slot of a ferromagnetic core and is ejected from the magnetic circuit. A signal is generated in a coil coupled in the magnetic circuit. The magnet and piston are restored to their initial positions by a reset spring and pneudraulic {sic} device. Velocities, voltages and currents are not specified.
U.S. Pat. No. 2,655,867 of Jordan discloses a quick-acting fuse of the inertia type employed in an ordnance missile to cause instantaneous detonation on impact. On discharge of the projectile, magnet 31 moves rearwardly inducing a voltage in coil 28 which is stored in condenser 41. On impact, the condenser instantaneously discharges through firing squib 42 and causes rapid detonation of the explosive charge.
U.S. Pat. No. 1,544,010 of Jordan discloses an apparatus for inducing currents via relatively slow back and forth displacement of a piston within a cylinder via a valving system which controls expansion of refrigeration gases. An exciting current from a utility line or a battery is utilized in conjunction with field windings and a soft iron member.
U.S. Pat. No. 3,105,153 of James, Jr. discloses a air-fuel mixture free-piston engine which continuously generates an alternating current. The piston has ring-shaped permanent magnets and the cylinder has surrounding coil windings 48 in which the alternating current signals are induced.
U.S. Pat. No. 1,785,643 of Noack et al. discloses another continuously driven free-piston type gasoline engine powered electrical generating system.
U.S. Pat. No. 3,206,609 of Dawes discloses another reciprocating engine driven electrical generator. Again the piston carries a magnet and a coil surrounds the cylinder.
U.S. Pat. No. 3,234,395 of Colgate discloses another electrical generating system driven by a free-piston engine fed with a fuel-air mixture that is ignited. Magnetic elements carried by the opposing pistons are moved back and forth through coils surrounding the common cylinder.
U.S. Pat. No. 3,247,40 of Toesca discloses yet another electrical generating system that uses a free-piston engine that burns a fuel-air mixture. An external voltage is required to activate the electromagnets that are employed.
U.S. Pat. No. 3,465,161 of Cutkosky discloses another generator using a reciprocating internal combustion engine and electromagnets.
U.S. Pat. No. 4,154,200 of Jarret et al. discloses another fuel/air mixture internal combustion free-piston engine with surrounding inductor coils.
U.S. Pat. No. 4,403,153 of Vallon discloses another fuel/air mixture internal combustion free-piston engine with surrounding coils for generating electricity.
U.S. Pat. No. 4,433,279 of Bhate discloses a free piston Stirling engine/alternator power unit.
U.S. Pat. No. 4,511,805 of Boy-Marcotte et al. discloses another Stirling engine powered electric generator.
The only pertinent prior art devices described above use an explosive to drive a solid heavy magnet past a coil, or visa versa, in a single linear movement. The devices are reusable so they tend to be relatively large and expensive. The magnets and coils are heavy. Therefore, the velocities attained, and the magnitudes of the voltages generated, are unnecessarily limited.